During drilling operations, measurements of downhole conditions taken while drilling can provide valuable information that may be used to by a drilling operator to improve efficiency and performance and minimize risk. Such measurements, when transmitted to the surface while drilling, may also provide an essentially real time view of changing downhole conditions allowing for essentially real time performance improvements and risk avoidance. There is considerable interest in the industry in risk avoidance since even relatively minor interruptions in drilling operations can be prohibitively expensive.
The recent introduction of Wired Drill Pipe (WDP) has significantly increased the communication bandwidth between downhole measurement sensors and the surface and therefore the total quantity of data that may be transmitted to the surface during a drilling operation. For example, measurement while drilling (MWD) and logging while drilling (LWD) data, including borehole imaging data, may be readily transmitted to the surface while drilling using WDP. Along string measurements (ASM), for example, including along string pressure and temperature measurements may also be transmitted to the surface during drilling.
While along string pressure and temperature measurements are known in the art, there has been no disclosure of methods for computing sequential and non-sequential pressure and temperature interval densities nor any methods of utilizing such interval densities to characterize the subterranean formations, the drilling fluid, or the drilling process. There remains a need in the art for further development.